text: The methylene blue value is defined as the number of milliliter's standard methylene value solution decolorized 0.1 g of activated carbon (dry basis).
  Methylene blue value reflects the amount of clay minerals in aggregate samples. In  materials science, methylene blue solution is successively added to fine aggregate which is being agitated in water.  The presence of free dye solution can be checked with stain test on a filter paper.